Olimex Development board for STM32F407ZGT6 CORTEX-M4 microcontroller STM32-H407 STM32-H407 User Manual

Product codes
STM32-H407
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OLIMEX© 2013
STM32-H407 user's manual
CHAPTER 5 CONTROL CIRCUITY AND HARDWARE MODULES
5. Introduction to the chapter
Here  you  can find information about reset circuit and quartz crystals locations, the power supply 
circuit is discussed.
5.1 Reset
STM32-H407's reset circuit includes R21 (10KΩ), R19 (1 KΩ), C35 (100nF) and a RESET button. 
5.2 Clocks
There are two quartz crystals available on the board:
12 MHz quartz crystal Q1 is connected to pins 23 and 24 of the CORTEX-M4F processor. 
Quartz crystal Q2 is a 32 768Hz RTC (real-time clock) and is connected to pins 8 and 9. 5.3 Power 
supply circuit
The power supply circuit of STM32-H407 allows flexible input supply from 6V to 16V direct 
current. This means a wide range of power supplies, adapters, converters are applicable. The 
maximum amperage the board can draw is 1A.
The Li-Po battery connector cannot be used to fully power the board. It's function is to give an 
option to save internal data if the board needs to be relocated. It will keep the RTC alive, for 
instance.
If you have successfully powered the board the red PWR LED will turn on. Note that it is possible   
to have the PWR LED on even if there isn't enough power for proper operation of the board and all 
the peripherals currently connected.
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